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Calc implicit differentiation

Hi, I've been attempting to do this question for a while now and do not know what I am getting wrong. It wants me to find y'(-3) by implicit differentiation given ln(x^2−8y)=x−y+4 and y(-3)=1 and to also find the equation to the tangent line to the curve at the point (-3,1). Any help is greatly appreciated!
Reply 1
Avatar for AsemaM
AsemaM
6
https://study.com/academy/answer/if-ln-x-2-8y-x-y-2-and-y-3-1-find-y-3-by-implicit-differentiation-thus-the-equation-of-the-tangent-line-to-the-graph-at-the-point-3-1-is-y.html
Hope this help.
Original post by AsemaM

they have got the wrong gradient at ( 3,1 )
Reply 3
Avatar for AsemaM
AsemaM
6
Original post by the bear
they have got the wrong gradient at ( 3,1 )

They just have positive 3. The question is almost the same, just plug in (-3,1) in y' (so it is gonna be your gradient m ) and find the equation of the tangent using y-1 = m(x+3)
Original post by AsemaM
They just have positive 3. The question is almost the same, just plug in (-3,1) in y' (so it is gonna be your gradient m ) and find the equation of the tangent using y-1 = m(x+3)

ikr, but they did it wrong using positive 3
Reply 5
Avatar for AsemaM
AsemaM
6
Original post by the bear
ikr, but they did it wrong using positive 3

What do you mean exactly? Maybe their question just had positive 3.
Original post by AsemaM
What do you mean exactly? Maybe their question just had positive 3.

they had the correct formula for y' but put in the numbers x = 3, y = 1 incorrectly
they should have got 5/7 instead of -5/9
Reply 8
Avatar for AsemaM
AsemaM
6
Original post by the bear
they had the correct formula for y' but put in the numbers x = 3, y = 1 incorrectly

I see what you mean, but did you get your question correct?

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